Hi Potilaracing, I have just had a word with Supertib and according to him the engine that s in the Hyper 7 (.28) is a piece of junk no matter what pipe you put on it so he advises you to go buy a better engine.
I have to say though that we have had Hyper 7's at our track befor and what Supertib said was what I was thinking seems how my GX.21 kicks ass against the .28 Hyper.28.(but thats to be expected as its tuned to kingdom come((a real screamer)).
There is however a .21 race engine offered by Hoboa that aint TO bad if your just thrashing your buggy around.
If you want a good engine that dont cost to much check out the GO engine line up,there great for the price.